Vishnu Avatar

This is the two part story where Brahama ji announces, Bhagwan Vishnu's Manushya avatar(incarnation), so that the Ravan & other Demons can be destroyed and Universe can be saved.
The Ramayana (Great Indian Sanskrit epic written by sage Valmiki ) .
It is ascribed to the Hindu sage Valmiki and forms an important part of the Hindu canon , considered to be itihasa. it depicts the duties of relationships, portraying ideal characters like the ideal father, the ideal brother, the ideal wife and the ideal king. It is a Epic of a victory of good over evil.
The descents of Vishnu are also integral to His teaching and tradition, whereas the accounts of other deities are not so strictly dependent on their avatar stories.